A press-fit, interference fit, or friction fit, is a physical fastening between two parts achieved by friction after the parts are pushed together, rather than by applying a fastener or adhesive. Press-fit connectors are used in the electronics industry by circuit board manufacturers, where press-fit connections allow a manufacturer to avoid, for instance, soldering a connector to a circuit board. In this context, a press-fit connection is typically formed when a pin is pressed into, or fitted into, a plated through-hole in the circuit board. The use of press-fit connectors in circuit board assemblies is pervasive today in the electronics industry.
Press-fit connectors can include solid pins or compliant pins. Today, most press-fit connectors use compliant pin technology, since the pins require less force during the insertion process, which causes less damage to the circuit board plated through-holes, and produces more reliable connections. Press-fit connectors are used in a variety of applications including, for instance, in data and communication applications. For many applications, the press-fit pins are continually becoming smaller. Due to ever-smaller features, the retention force and seal of the press-fit pin to the plated through-hole is becoming more susceptible to failure.